The behavior of plasma
atrial natriuretic factor (
ANF) and
digoxin-like substance (DLS), and the daily urinary excretion of
kallikrein (uKK) were evaluated in young hypertensives and in young normotensives with or without a family history of
essential hypertension. Each group was also evaluated, separating those with low plasma
renin activity from the total sample. The sample group was made up of 75 young males; 31 hypertensives (mean age 22.7 +/- 2.5 years), 28 normotensives with hypertensive heredity (normotensives F+) (mean age 22.2 +/- 1.9 years) and 16 normotensives (mean age 22.0 +/- 2.1 years). An inverse correlation between
ANF and PRA was shown in all groups. In hypertensives,
ANF was inversely correlated with uKK (r = -0.664, P less than .0001). Plasma
ANF (P less than .012) and DLS (P less than .0001) were higher in hypertensives than in normotensives, while uKK excretion was lower (P less than .0001). Plasma levels of DLS were higher in F+ normotensives than in normotensives (P less than .003). Low
renin hypertensives showed the lowest uKK excretion (P less than .0001 v normal-high
renin hypertensives). Furthermore, low
renin hypertensives showed the highest plasma levels of
ANF (P less than .0001 v normal high
renin hypertensives) and DLS (P less than .012 v normal-high
renin hypertensives). Plasma
ANF (P less than .0001) was higher, while uKK was lower (P less than .045) in low
renin F+ normotensives than in normal-high
renin ones. In conclusion, our data indicate that plasma
ANF and DLS are elevated since the early phase of
hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)